<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
    <script type="text/javascript" src="../jquery-1.7.2.js"></script>
    <script type = "text/javascript">
    $(function(){
        var btnObj = $("#btn");
        btnObj.click(function(){
            alert("Hello");
        })
    })
    </script>
</head>
<body>
    <button id = "btn" >Hello</button>
</body>
</html>